This invention is directed to a problem in uniformly applying a thermally conductive interface material (TIM) between an electronic device and an enclosing metal lid or cover. Additionally, the method of application of the thermal material taught here creates a low stress bond between the device and lid, reducing potential of damage to the device.
Known solutions include attaching and bonding a TIM between a lid and an electronic device, typically in a limited coverage area. The TIM is applied either to the inside of the lid or to the surface of the device, and then the lid and electronic device substrate are mated together at the edges of the lid sides. Force is applied typically to the top of the lid to make contact between the lid, the substrate, the TIM and the electronic device simultaneously.
This creates a challenge to manage all surface contacts due to non-planarity on any given surface (lid, TIM, substrate, electronic device), resulting in non-attached areas either between the lid sides and the substrate, the inner side of the lid and TIM, or between the TIM and the electronic device surface. An inadequate attachment can create either environmental or structural damage to the device(s) being packaged, or functional damage to the device due to poor thermal conductivity between the heat source (electronic device) and the lid.